Synthesis of Aspirin

Conclusions:
The percentage yield of aspirin (C9H8O4) is 90,9%.
The resulting aspirin is pure since the addition of FeCl3 does not change the color of solution.
Phenols (such as salicylic acid) react with ferric chloride (Iron (III) chloride) to form colored (blue or violet) complexes. However, aspirin does not have phenol group, therefore it does not form a purple complex.
Crystallization is the way how to separate two or more substances. It is based on 1) different solubility of the substances, 2) solubility dependence on the temperature.
The esterification reaction is an effective way of obtaining aspirin in laboratory circumstances.
…